Free download enables DreamScene in all versions of Windows 7
DreamScene enabled you to set a video file as your wallpaper -- which is cool, though I found it terribly distracting. A bit too much like trying to work atop a YTMND page for my liking, though maybe I was choosing the wrong kind of videos. DreamScene had plenty of fans, however, and they were disappointed when Microsoft axed the feature in Windows 7.
Fortunately, the ever-helpful Kishan Bagaria has provided yet another tool to help you out. Download DreamScene Activator and run the correct .exe for your version of Windows 7 (either 32 or 64-bit) and you'll be able to enjoy videos-as-wallpaper once more! Activator will also add the play/pause control to the Windows desktop right-click context menu.
Just remember to right-click and run the activator as administrator, or it probably won't work.